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arXiv · 1810.11170

Scaling Laws for the Propulsive Performance of Three-Dimensional Pitching Propulsors

Fatma Ayancik·Qiang Zhong·Daniel B. Quinn·Aaron Brandes·Hilary Bart-Smith·Keith W. Moored
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Abstract

Scaling laws for the thrust production and energetics of self-propelled or fixed-velocity three-dimensional rigid propulsors undergoing pitching motions are presented. The scaling relations extend the two-dimensional scaling laws presented in Moored & Quinn (2018) by accounting for the added mass of a finite-span propulsor, the downwash/upwash effects from the trailing vortex system of a propulsor, and the elliptical topology of shedding trailing-edge vortices. The novel three-dimensional scaling laws are validated with self-propelled inviscid simulations and fixed-velocity experiments over a range of reduced frequencies, Strouhal numbers and aspect ratios relevant to bio-inspired propulsion. The scaling laws elucidate the dominant flow physics behind the thrust production and energetics of pitching bio-propulsors, and they provide guidance for the design of bio-inspired propulsive systems.

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Fatma Ayancik, Qiang Zhong, Daniel B. Quinn, Aaron Brandes, Hilary Bart-Smith, Keith W. Moored. 2018-10-26. Scaling Laws for the Propulsive Performance of Three-Dimensional Pitching Propulsors. https://doi.org/10.1017/jfm.2019.334

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